Abstract: A magnetic field vector sensor includes a substrate parallel to a plane, a support mobile relative to it and rotatable about a vertical rotation axis perpendicular to it, a magnetic field source generating a field having a moment in a non-perpendicular direction, the source being fixed to the support with no degree-of-freedom to exert torque on the support when a field to be measured is present, the field being non-collinear with the moment, a transducer to convert torque exerted on the support into a field amplitude of a component of the field along a measurement axis in the plane, wherein the source comprises a magnetostrictive permanent magnet for generating the field having a moment whose direction varies with stress on the magnet, and wherein the sensor further comprises a controllable device to reversibly modify the moment direction, and a stress generator to vary stress and hence moment direction.

Abstract: A method for quasi-static testing a magnetic recording head read sensor is described. The method includes applying a first voltage to a heater in the magnetic recording head and measuring an output of the magnetic recording head read sensor while applying the first voltage to the heater and recording the measured output as a first set of measurements. The method further includes applying a second voltage to the heater in the magnetic recording head and measuring the output of the magnetic recording head read sensor while applying the second voltage to the heater and recording the measured output as a second set of measurements. The first and second sets of measurements are then compared.

Abstract: A magnetoresistive angular sensor and sensing method, in which an external magnetic field generator is used to provide a first mode in which a dc external magnetic field is provided in a predetermined direction and which dominates over the magnetic field generated by the input device being sensed. In a second mode, the external magnetic field is smaller. The angular sensor arrangement outputs from the two modes are combined, and this enables the input device angular orientation to be determined with offset voltage compensation.

Abstract: A magnetic sensor includes a magnetic layer comprising magnetic material and a grain refining agent. The magnetic layer having a grain-refined magnetic layer surface. A layer adjacent the magnetic layer has a layer surface that conforms to the grain-refined magnetic layer surface.

Abstract: The present invention discloses a design for a single-chip dual-axis magnetic field sensor, based on magnetic tunnel junction (MTJ) elements and permanent magnets integrated on a semiconductor substrate to produce two types of sensor bridges that detect orthogonal magnetic field components. The orthogonal magnetic field component detection capability results from the different types of sensor bridges that can be produced by varying the shape of the MTJ elements and the bias fields that can be created by permanent magnets. Because the permanent magnets can create orthogonal bias fields on the different sensor bridges, it is possible to use a single pinned layer to set direction for both sensor bridges. This is advantageous because it permits the two-axis sensor to be fabricated on a single semiconductor chip without the need for specialized processing technology such as local heating, or deposition of multiple magnetoresistive films with different pinned layers setting directions.

Abstract: Embodiments related to magnetoresistive angle sensor layouts having reduced anisotropic magneto resistance (AMR) effects. Embodiments provide magnetoresistive angle sensor layouts that reduce or eliminate distortion related to AMR effects, can be more easily scaled up or down, and are more compact to use available surface area more efficiently.

Abstract: The present invention discloses a design of a single-chip push-pull bridge sensor, composed of magnetoresistive elements, utilizing on-chip permanent magnets. The permanent magnets are oriented to preset magnetization directions of free layers of adjacent sensor bridge arms so that they point to different directions with respect the same sensing direction, enabling push-pull operation. The push-pull bridge sensor of the present invention is integrated on a single chip. Additionally, an on-chip coil is disclosed to reset or calibrate the magnetization directions of the free layers of the magnetoresistive elements.

Abstract: A magnetic sensor device includes a first magnet and a second magnet that are disposed on mutually opposing sides of a conveyance path, and one of poles of the first magnet faces an opposite pole of the second magnet. The first magnet and the second magnet generate a cross magnetic field whose strength in a spacing direction, which is orthogonal to a conveying direction, is within a predetermined range. An AMR element is located in a magnetic field in which the strength of the cross magnetic field in the spacing direction is within a predetermined range, and detects, as change in a resistance value, change in the cross magnetic field caused by an object to be detected. A multilayer board outputs the change in the resistance value detected by the AMR element to a processing circuit.

Abstract: Embodiments relate to magnetoresistive (xMR) sensors which provide a yaw angle between a reference premagnetization direction of the sensor layer and the magnetic field to be detected, or between a direction of a bias magnetic field and the magnetic field to be detected. In an embodiment, an xMR sensor is rotated or tilted with respect to a direction of a magnetic field to be sensed such that a premagnetization direction of the reference premagnetization layer of the xMR sensor is also rotated or tilted at some yaw angle with respect to the direction of the magnetic field. In another embodiment, a bias magnet or other source is used with sensors not having premagnetization or reference layers, such as anisotropic magnetoresistive (AMR) sensors, and the direction of the bias magnetic field is also tilted or rotated with respect to the direction of the magnetic field to be detected.

Abstract: An apparatus and a method for the contactless detection of vehicles via one or more magnetometers for measuring the geomagnetic field, in which at least one magnetometer includes a device for measuring the gravitational field.

Abstract: The integrated magnetic sensor for detecting an external magnetic field, is formed by a body of semiconductor material having a surface; an insulating layer covering the body of semiconductor material; a magnetically sensitive region, for example a Hall cell, extending inside the body; and a concentrator of ferromagnetic material, extending on the Hall cell and having a planar portion extending parallel to the surface of the substrate on the insulating layer. The concentrator terminates with a tip protruding peripherally from, and transversely to, the planar portion toward the Hall cell. When the magnetically sensitive region is a sensing coil of a fluxgate sensor, it is formed on the substrate, embedded in the insulating layer, and the tip of the concentrator can reach as far as the sensing coil.

Abstract: A device is provided. The device may include a first electrical connector, a second electrical connector, an interconnect, and a magnetic field detector. The interconnect is mounted in electrical contact with the first electrical connector and the second electrical connector and includes a loop. The magnetic field detector is located in proximity to the loop of the interconnect. The magnetic field detector is located to detect a current flowing in the interconnect when the current flows in the interconnect.

Abstract: A magnetic-field sensor includes: a chip including a substrate having a first surface and an insulating layer covering the first surface; first and second magnetoresistors each extending into the insulating layer and having a main axis of magnetization and a secondary axis of magnetization; a first magnetic-field generator configured to generate a first magnetic field having field lines along the main axis of magnetization of the first magnetoresistor; a second magnetic-field generator configured to generate a second magnetic field having field lines along the main axis of magnetization of the second magnetoresistor. The main axes of magnetization extending transversely to each other and the secondary axes of magnetization extending transversely to each other. The first and second magnetoresistors extend into the insulating layer at a first distance and a second distance, respectively, that differ from one another, from the first surface.

Abstract: A tunneling magnetoresistance sensor including a substrate, an insulating layer, a tunneling magnetoresistance component and an electrode array is provided. The insulating layer is disposed on the substrate. The tunneling magnetoresistance component is embedded in the insulating layer. The electrode array is formed in a single metal layer and disposed in the insulating layer either below or above the TMR component. The electrode array includes a number of separate electrodes. The electrodes are electrically connected to the tunneling magnetoresistance component to form a current-in-plane tunneling conduction mode. The tunneling magnetoresistance sensor in this configuration can be manufactured with a reduced cost and maintain the high performance at the same time.

Abstract: The current in a generator circuit breaker is measured using the Faraday effect of an optical sensing fiber looped around the breaker's conductor. The sensing fiber is arranged in a sensing strip, which can be mounted to the enclosure of the generator circuit breaker or to the conductor. Exemplary embodiments can have a wide measuring range and can easily be fitted to new or existing generator circuit breakers.

Abstract: An object of the present invention is to provide a magnetic sensor simply configured so as to magnetically measure not only conductive materials but also nonconductive materials over a wide temperature range and which offers high performance and high reliability, as well as a scanning microscope that uses the magnetic sensor. A scanning microscope according to the present invention includes a magnetic sensor with a magnetic sensing element provided at a free end of a cantilever-like flexible member and a strain gauge installed on the flexible member, driving means for driving the flexible member or a measurement sample, and control means for controlling driving provided by the driving means based on an output signal from the strain gauge.

Abstract: The invention concerns a current transducer for measuring a current flowing through a cable, comprising at least one magnetic field sensor and an electronic circuit. The current transducer comprises a head with a ferromagnetic core optimized to reduce the effects of external magnetic fields. The invention further concerns a magnetic transducer comprising a magnetic field sensor and an electronic circuit. The electronic circuit comprises at least one current source, a transformer, a fully differential preamplifier coupled to the transformer, a phase sensitive detector coupled to the preamplifier and a logic block configured to operate the magnetic field sensor(s) to provide an AC output voltage. The magnetic field sensor(s) is preferably either a Hall element or an AMR sensor or a flux-gate sensor.

Abstract: A magnetic sensor includes first and second MR elements, and an electrode electrically connecting the first and second MR elements to each other. The electrode includes a first portion having a first surface, a second portion having a second surface, and a coupling portion coupling the first and second portions to each other. The first surface is in contact with an end face of the first MR element. The second surface is in contact with an end face of the second MR element. Each of the first and second surfaces has a three-hold or higher rotationally symmetric shape. The diameter of a first inscribed circle inscribed in the outer edge of the first surface and the diameter of the second inscribed circle inscribed in the outer edge of the second surface are greater than the width of the coupling portion.

Abstract: A magnetoresistive sensor including: a first pinned-magnetization magnetic layer, called pinned layer; a free-magnetization magnetic layer, called sensitive layer, of which the magnetization, in the absence of an external field, is substantially orthogonal to the magnetization of the pinned layer, the pinned and sensitive layers being separated by a first separating layer for magnetic uncoupling; and a layer, called lateral coupling layer, located on the side of the sensitive layer opposite that of the separating layer, the lateral coupling layer serving to control the lateral spin transfer.

Abstract: A sensor assembly is provided for use in tracking a medical device. The sensor assembly comprises a magnetoresistance sensor capable of providing position and orientation information. In certain implementations, the magnetoresistance position and orientation sensor is originally configured for connection to a substrate using one type of interconnect approach but is modified to be connected using a different interconnect approach.

Abstract: An integrated magnetic field generation and detection platform is described that is capable of manipulating and detecting individual magnetic particles, such as spherical super-paramagnetic beads, and providing biosensing functionality. The platform is implemented in an integrated circuit, a portion of the surface of which is functionalized with one or more biochemical agents that binds tightly (i.e., specifically) with a target analyte. The magnetic beads are similarly functionalized with one or more biochemical agents that that bind specifically with the target analyte. When a sample is introduced, magnetic beads that specifically bind to the integrated circuit can be separated from non-specifically bound beads and detected.

Abstract: Embodiments related to the generation of magnetic bias fields for a magneto sensor are described and depicted.

Abstract: Embodiments relate to magnetoresistive sensors suitable for both angle and field strength sensing. In an embodiment, a sensor comprises two different magnetoresistive (xMR) sensor components for sensing two different aspects or characteristics of a magnetic field. In an embodiment, the first xMR sensor component is configured for magnetic field angle or rotation sensing, while the second xMR sensor component is configured for magnetic field strength sensing. In an embodiment, the second xMR sensor component is configured for magnetic field strength sensing in two dimensions. The second xMR sensor therefore can determine, in embodiment, whether the field sensed with respect to angle or rotation by the first xMR sensor component is of sufficient strength or meets a minimum magnitude threshold. If the minimum threshold is not met, an alarm or alert can be provided.

Abstract: In one aspect of the present invention, the semiconductor device is a bipolar magnetic junction transistor (MJT), and includes a first non-magnetic semiconductor layer, a second non-magnetic semiconductor layer, and a magnetic semiconductor layer. The first non-magnetic semiconductor layer has majority charge carriers of a first polarity. The second non-magnetic semiconductor layer is disposed adjacent to the first non-magnetic semiconductor layer such that a first junction is formed at a first interface region between the first non-magnetic semiconductor layer and the second non-magnetic semiconductor layer. The magnetic semiconductor layer has majority charge carriers of the first polarity, and is disposed adjacent to the second non-magnetic semiconductor layer such that a second junction is formed at a second interface region between the second non-magnetic semiconductor layer and the magnetic semiconductor layer.

Abstract: The present invention relates to a magnetic field sensing device (50) comprising several functionally different layers (38, 60, 70), wherein a Wheatstone bridge layer (70) comprises at least two resistors (20) of a Wheatstone bridge (18), each resistor (20) comprises at least one magnetic field sensing element (10) in the form of a resistor subelement (22), and a flip conductor layer (38) comprising at least one flip conductor (30) for flipping the internal magnetization state of each magnetic field sensing element (10). The flip conductor (30) comprises a plurality of conductor stripes (32) being arranged on at least two different flip conductor sublayers (38-1, 38-2) of said flip conductor layer (38) and being electrically coupled with each other through vias.

Abstract: Disclosed herein are an apparatus and a method for detecting a crack. The apparatus includes a power supply unit, a sensor module, and a signal reception module. The power supply unit supplies power. The sensor module receives the input power from the power supply unit, and outputs sensing power corresponding to the magnetic field of an object to be measured. The signal reception unit converts the sensing power output from the sensor module into a quantitative value, and computes the distribution of the magnetic field. The sensor module includes a first sensor array configured to detect magnetic field vectors in a direction vertical to a sensor surface, and a second sensor array placed on the first sensor array in an overlapping manner and configured to detect magnetic field vectors in a direction lateral with respect to the sensor surface.

Abstract: A magnetic sensor includes a spin valve-type magneto-resistive element, a voltage detection part, a coil, and a current control part, the coil being configured to apply a measuring magnetic field to the spin valve-type magneto-resistive element upon application of a current, the voltage detection part being configured to output a detection signal to the current control part upon detecting an output voltage of the spin valve-type magneto-resistive element reaching a predetermined voltage value, the current control part being configured to control the current to unidirectionally increase or unidirectionally decrease a strength of the measuring magnetic field from an initial value, but upon input of the detection signal, control the current to return the strength of the measuring magnetic field to the initial value, the initial value being a magnetic field strength where the spin valve-type magneto-resistive element reaches saturation magnetization.

Abstract: A current sensor includes first and second magnetic sensors that are placed around a current line through which a current flows so that the current line is positioned therebetween, and that detect an induction field generated by the current. Each of the first and second magnetic sensors has a main sensitivity axis and a sub-sensitivity axis. The direction of the main sensitivity axis of each of the first and second magnetic sensors is oriented in a direction that is not orthogonal to the direction of the induction field. The directions of the main sensitivity axes of the first and second magnetic sensors are oriented in the same direction and the directions of the sub-sensitivity axes are oriented in the same direction, or the directions of the main sensitivity axes are oriented in opposite directions and the directions of the sub-sensitivity axes are oriented in opposite directions.

Abstract: An integrated circuit includes a magnetic field sensor and an injection molded magnetic material enclosing at least a portion of the magnetic field sensor.

Abstract: An MI sensor element 1 includes a substrate 4 formed of a non-magnetic material, a plurality of magneto-sensitive bodies 2, and a plurality of detecting coils 3. The plurality of magneto-sensitive bodies 2 are formed of an amorphous material, and are fixed on the substrate 4, and are electrically connected to each other. The detecting coils 3 are wound around each of the magneto-sensitive bodies 2, and are electrically connected to each other. The MI sensor element 1 outputs a voltage corresponding to a magnetic field strength acting on the magneto-sensitive bodies 2 from the detecting coil 3 by flowing a pulse current or a high-frequency current to the magneto-sensitive body 2. The plurality of magneto-sensitive bodies 2 are formed by fixing one amorphous wire 20 on the substrate 4, and then cutting the wire.

Abstract: An AMR sensor, comprises at least first and second AMR sensor elements to which opposite bias fields are applied. The first and second AMR sensor element outputs are combined to derive a sensor response which is substantially anti-symmetric in the region close to zero external magnetic field. This arrangement shifts the zero detection point of the AMR sensor elements away from a maximum of the response curve, so that sensitivity in proximity to a zero input field is obtained. To overcome the problem that the response is not anti-symmetric, the signals from (at least) two sensor elements are combined.

Abstract: A structure and method are provided for self-test of a Z axis sensor. Two self-test current lines are symmetrically positioned adjacent, but equidistant from, each sense element. The vertical component of the magnetic field created from a current in the self-test lines is additive in a flux guide positioned adjacent, and orthogonal to, the sense element; however, the components of the magnetic fields in the plane of the sense element created by each of the two self-test current line pairs cancel one another at the sense element center, resulting in only the Z axis magnetic field being sensed during the self-test.

Abstract: A magnetometer with a set/reset coil having portions that cross portions of sensing strips at an angle in order to create a magnetic field in the sensing strip that is at an angle with respect to the easy axis of magnetization of the sensing strip. Each sensing strip may have a portion having a magnetic field created therein that is different from a magnetic field created in another portion of the same sensing strip. As a result, a lower set/reset coil current is needed to initialize the magnetometer.

Abstract: Embodiments relate to integrated sensors and sensing methods. Embodiments relate to integrated sensor layouts. Embodiments are configured to maximize a ratio of sensor spacing over a die area. While being generally applicable to many different types of sensors, particular advantages can be presented for magnetoresistive (xMR) sensors.

Abstract: A magnetoresistive sensor bridge utilizing magnetic tunnel junctions is disclosed. The magnetoresistive sensor bridge is composed of one or more magnetic tunnel junction sensor chips to provide a half-bridge or full bridge sensor in a standard semiconductor package. The sensor chips may be arranged such that the pinned layers of the different chips are mutually anti-parallel to each other in order to form a push-pull bridge structure. The sensor chips are then interconnected using wire bonding. The chips can be wire-bonded to various standard semiconductor leadframes and packaged in inexpensive standard semiconductor packages. The bridge design may be push-pull or referenced. In the referenced case, the on-chip reference resistors may be implemented without magnetic shielding.

Abstract: There is provided a current sensor capable of performing malfunction determination with high accuracy even under the influence of an adscititious magnetic field. A current sensor includes first and second current sensor units, a computation unit, a storage unit, and a determination processing unit. The first current sensor unit measures a target current. The first and second current sensor units have almost the same sensitivity. The computation unit calculates and outputs an addition value and a difference value of outputs of the first and second current sensor units. In the storage unit, the addition and difference values output from the computation unit are stored. The determination processing unit determines whether a malfunction has occurred by using the addition and difference values stored in the storage unit. The determination processing unit determines that a malfunction has occurred, in a case where there is a correlation between the addition and difference values.

Abstract: A magnetic sensor has a bottom shield layer, an upper shield layer, and a sensor stack adjacent the upper shield layer. The sensor includes a seed layer between the bottom shield layer and an antiferromagnetic layer of the sensor stack. The seed layer has a magnetic layer adjacent the sensor stack and a nonmagnetic layer adjacent the bottom shield layer.

Abstract: A method and structure for a three-axis magnetic field sensing device is provided. The device includes a substrate, an IC layer, and preferably three magnetic field sensors coupled to the IC layer. A nickel-iron magnetic field concentrator is also provided.

Abstract: Devices for sensing current are described herein. One device includes a first magnetic sensor configured to determine a first magnetic field associated with a current conductor while the current conductor is conducting a current, a second magnetic sensor, a particular distance from the first magnetic sensor, configured to determine a second magnetic field associated with the current conductor while the current conductor is conducting the current, and a fastener configured to secure the current sensor to the current conductor such that the first and second magnetic sensors are on a plane substantially perpendicular to a longitudinal axis of the current conductor.

Abstract: Embodiments of the present invention provide a magnetic field sensor. The magnetic field sensor includes at least four XMR elements connected in a full bridge circuit including parallel branches. The at least four XMR elements are GMR or TMR elements (GMR=giant magnetoresistance; TMR=tunnel magnetoresistance). Two diagonal XMR elements of the full bridge circuit include the same shape anisotropy, wherein XMR elements in the same branch of the full bridge circuit include different shape anisotropies.

Abstract: A current sensor including a magnetic detecting bridge circuit which is constituted of four magneto-resistance effect elements with a resistance value varied by application of an induced magnetic field from a current to be measured, and which has an output between two magneto-resistance effect elements. The four magneto-resistance effect elements have the same resistance change rate, and include a self-pinned type ferromagnetic fixed layer which is formed by anti-ferromagnetically coupling a first ferromagnetic film and a second ferromagnetic film via an antiparallel coupling film therebetween, a nonmagnetic intermediate layer, and a soft magnetic free layer. Magnetization directions of the ferromagnetic fixed layers of the two magneto-resistance effect elements providing the output are different from each other by 180°. The magnetic detecting bridge circuit has wiring symmetrical to a power supply point.

Abstract: An MR sensor arrangement is integrated with an IC. A metal layer of the IC structure (e.g. CMOS) is patterned to define at least first and second contact regions. Metal connecting plugs are provided below the first and second contact regions of the metal layer for making contact to terminals of the integrated circuit. A magnetoresistive material layer is above the metal layer and separated by a dielectric layer. Second metal connecting plugs extend up from the metal layer to an MR sensor layer. The sensor layer is thus formed over the top of the layers of the IC structure.

Abstract: Embodiments related to giant magneto resistance (GMR) angle sensor layouts having reduced anisotropic magneto resistance (AMR) effects. Embodiments provide GMR angle sensor layouts that reduce or eliminate distortion related to AMR effects, can be more easily scaled up or down, and are more compact to use available surface area more efficiently.

Abstract: An illustrative packaged magnetic field sensor includes a power input terminal and a sensor output terminal, both accessible from outside of the package housing. A sensing block is situated in the package housing and electrically coupled to the magnetic field sensing device and the sensor output terminal. An adjustment block is situated in the package housing and coupled to the power input terminal and the sensing block. In some cases, the adjustment block may receive one or more messages that include sensor adjustment information. The one or more messages may be modulated onto the power input signal. The adjustment block may decode the received sensor adjustment information from the messages, and store the decoded adjustment information into a memory. The adjustment block may then adjust the output signal of the sensing block based on the decoded adjustment information.

Abstract: A transducer is disclosed for detecting the AC and DC voltage difference between two nodes in an electrical circuit and electronically transmitting the measured voltage difference to an electrical system that is electrically isolated from the common mode potential of the two nodes. The voltage drop between two points in a circuit under test is determined by detecting the current flowing through a resistive shunt coil connected in parallel to the test points. Current through the resistive shunt coil is linearly proportional to the voltage difference between the test points, and it is detected by using a magnetic sensor that is separated from the shunt coil by an insulating dielectric barrier. The transducer can be packaged in a standard integrated circuit package in order to provide a small and low cost voltage transducer for test, measurement, control, and signal-isolation applications.

Abstract: A current sensor includes a substrate, a conductive body being provided above the substrate and extending in one direction, and magnetoresistance effect elements being provided between the substrate and the conductive body and outputting output signals owing to an induction magnetic field from a current to be measured being conducted through the conductive body, wherein each of the magnetoresistance effect elements has a laminated structure including a ferromagnetic fixed layer whose magnetization direction is fixed, a non-magnetic intermediate layer, and a free magnetic layer whose magnetization direction fluctuates with respect to an external magnetic field, the ferromagnetic fixed layer is a self-pinned type formed by antiferromagnetically coupling a first ferromagnetic film and a second ferromagnetic film through an antiparallel coupling film, the Curie temperatures of the first ferromagnetic film and the second ferromagnetic film are approximately equal, and a difference between the magnetization amounts

Abstract: A multi-axis GMR or TGMR based magnetic field sensor system is disclosed. Preferably a three axis sensor system is provided for sensing magnetic flux along three mutually orthogonal axes, which can be used for magnetic compass or other magnetic field sensing applications. The sensing units are operative to sense X and Y axis magnetic flux signals in the device (XY) plane, while Z axis sensitivity is achieved by use of a continuous ring shaped or octagonal magnetic concentrator that is adapted to convert the Z axis magnetic flux signal into magnetic flux signals in the XY plane.

Abstract: A disclosed magnetic sensor includes a substrate having a plane surface and multiple sloping surfaces; multiple soft magnetic films each disposed on a different one of the sloping surfaces and magnetized according to strength of a magnetic field; and multiple detecting devices each disposed on the plane surface, including a free layer and a pinned layer and configured to produce a detection output according to magnetization of the free layer and the pinned layer. Each of the soft magnetic films is magnetically coupled with the free layer of a different one of the detecting devices. The pinned layers of the detecting devices have magnetization directions different from each other.

Abstract: A magnetic sensor of the present invention includes a magnetoresistive element having a sensitivity axis in a specified direction, the magnetoresistive element having a laminated structure including a ferromagnetic pinned layer having a pinned magnetization direction, a nonmagnetic intermediate layer, a free magnetic layer having a magnetization direction varying with an external magnetic field, and an antiferromagnetic layer which applies an exchange coupling magnetic field to the free magnetic layer.

Abstract: A measuring method measuring a resistance of a resistor of a magnetic sensor that includes the resistor is provided. The method includes a step of measuring an output voltage of the magnetic sensor in an AC magnetic field, a step of measuring a first combined resistance of the MR element and the resistor in no magnetic field, a step of measuring a second combined resistance of the MR element and the resistor in a constant magnetic field of which a direction and strength are substantially the same as a magnetic field, a step of measuring a third combined resistance of the MR element and the resistor in another constant magnetic field of which a direction and strength are substantially the same as another magnetic field, and a step of calculating the resistance of the resistor based on the output voltage, the first, second and third combined resistance.